Retainers for transcatheter heart valve delivery systems

ABSTRACT

A delivery device  10  for a collapsible prosthetic heart valve includes a catheter assembly  16  including a shaft  26  around which a compartment  23  is defined, the compartment  23  being adapted to receive the valve in an assembled condition, and a retainer  30  including a pusher  32  and a holder  34  adapted to retain a stent portion  106  of the valve. The catheter assembly  16  also includes a distal sheath  24  adapted to selectively cover and uncover the compartment  23  and the valve, the distal sheath  24  extending around the shaft  26  at least when the distal sheath  24  covers the compartment  23.  The pusher  32  includes one or more recesses  40  in a retention edge  33  thereof, each recess  40  being adapted to receive a junction  107  at an end of the stent portion  106  of the valve. The holder  34  includes one or more elongated ribs  50,  each rib  50  being adapted to fit into a cell opening  108  of the stent portion  106  of the valve.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. application Ser. No.13/823,337, filed on Jul. 10, 2013, which is a national phase entryunder 35 U.S.C. §371 of International Application No. PCT/US2011/001596filed on Sep. 16, 2011, published in English, which claims the benefitof U.S. Provisional Patent Application No. 61/384,014, filed on Sep. 17,2010, the disclosures of which are hereby incorporated herein byreference.

BACKGROUND OF THE INVENTION

The present invention is related to prosthetic heart valve replacement,and more particularly to devices, systems, and methods for transcatheterdelivery of collapsible prosthetic heart valves for deployment in apatient.

Prosthetic heart valves that are collapsible to a relatively smallcircumferential size can be delivered into a patient less invasivelythan valves that are not collapsible. For example, a collapsible valvemay be delivered into a patient via a tube-like delivery apparatus suchas a catheter, a trocar, a laparoscopic instrument, or the like. Thiscollapsibility can avoid the need for a more invasive procedure such asfull open-chest, open-heart surgery.

Collapsible prosthetic heart valves typically take the form of a valvestructure mounted on a stent. There are two types of stents on which thevalves structures are ordinarily mounted: self-expanding stents andballoon-expandable stents. To place such valves into a deliveryapparatus and ultimately into a patient, the valve must first becollapsed or crimped to reduce its circumferential size.

When a collapsed prosthetic valve has reached the desired implant sitein the patient (e.g., at or near the annulus of the patient's heartvalve that is to be replaced by the prosthetic valve), the prostheticvalve can be deployed or released from the delivery apparatus andexpanded to full operating size. For balloon-expandable valves, thisgenerally involves releasing the entire valve, assuring its properlocation, and then expanding a balloon positioned within the valvestent. For self-expanding valves, on the other hand, the stentautomatically begins to expand as the sheath covering the valve iswithdrawn.

In conventional delivery systems for self-expanding aortic valves, afterthe delivery system has been positioned for deployment, the annulus endof the valve is typically unsheathed and expanded into engagement withthe valve annulus, while the aortic end of the valve remains sheathed.Once the annulus end of the valve has expanded, it may be determinedthat the valve needs to be repositioned in the patient's valve annulus.To accomplish this, a user (such as a surgeon or an interventionalcardiologist) typically resheathes the annulus end of the valve, so thatthe valve can be repositioned while in a collapsed state. After thevalve has been repositioned, the user can again unsheathe the valve fordeployment.

Once a self-expanding valve has been fully deployed, it expands to adiameter larger than that of the sheath that previously retained thevalve in the collapsed condition, making resheathing impossible, ordifficult at best. In order for a user to be able to resheathe apartially-deployed valve, a portion of the valve must still be collapsedinside of the sheath.

Despite the various improvements that have been made to the collapsibleprosthetic heart valve delivery process, conventional delivery devices,systems, and methods suffer from some shortcomings For example, inconventional delivery devices for self-expanding valves, the valve maybe held in a compartment of the device by the engagement of retentionmembers on the stent with one or more retainers in the compartment.During deployment of the valve into the desired area (e.g., the valveannulus), the high frictional force produced during unsheathing of thevalve may cause high axial forces to be applied directly to the stentretention members, which may damage or deform the stent struts thatsupport the retention members.

There therefore is a need for further improvements to the devices,systems, and methods for transcatheter delivery of collapsibleprosthetic heart valves. Among other advantages, the present inventionmay address one or more of these needs.

BRIEF SUMMARY OF THE INVENTION

Delivery devices for a collapsible prosthetic heart valve and a methodof delivering a collapsible prosthetic heart valve are disclosed.

A delivery device for a collapsible prosthetic heart valve includes acatheter assembly including a principal shaft around which a compartmentis defined, the compartment being adapted to receive the valve in anassembled condition, the catheter assembly further including a distalsheath adapted to selectively cover and uncover the compartment and thevalve, the distal sheath extending around the principal shaft at leastwhen the distal sheath covers the compartment, and a retainer, includinga pusher having at least one recess in a retention edge thereof, therecess being adapted to receive a junction at an end of a stent portionof the valve, and a holder having at least one elongated rib adapted tofit into a cell opening in the stent portion of the valve.

The pusher may be slidable relative to the holder along a longitudinalaxis of the delivery device. The holder may be slidable relative to thepusher along a longitudinal axis of the delivery device. The at leastone recess may be shaped to substantially match the shape ofoutward-facing surfaces of the junction. The at least one rib may have awidth in a circumferential direction, an end of the rib relatively closeto the pusher may have a first width and an end of the rib relativelyfar from the pusher may have a second width greater than the firstwidth, such that the rib may be shaped to substantially match the shapeof inward-facing surfaces of the cell opening contacted by the rib. Theat least one rib may have a cross-sectional shape in a circumferentialdirection that includes an undercut. The at least one recess may have across-sectional shape in a circumferential direction that includes anundercut.

The at least one recess may be a continuous annular channel formed inthe retention edge of the pusher adjacent a circumference of the pusher.The principal shaft may be affixed to the holder, and the deliverydevice may also include a pusher shaft affixed to the pusher andextending along a longitudinal axis of the delivery device outside ofthe principal shaft. The delivery deice may also include a locking pinadapted to temporarily affix the principal shaft to the pusher shaft sothat the distal sheath may be slidable along the longitudinal axisrelative to the affixed principal shaft and pusher shaft. The principalshaft may be affixed to the holder, and the delivery device may alsoinclude a pusher shaft affixed to the pusher and extending along alongitudinal axis of the delivery device inside of the principal shaft.The delivery deice may also include a locking pin adapted to temporarilyaffix the principal shaft to the pusher shaft so that the distal sheathmay be slidable along the longitudinal axis relative to the affixedprincipal shaft and pusher shaft.

A delivery device for a collapsible prosthetic heart valve includes acatheter assembly including a principal shaft around which a compartmentis defined, the compartment being adapted to receive the valve in anassembled condition, the catheter assembly further including a distalsheath adapted to selectively cover and uncover the compartment and thevalve, the distal sheath extending around the principal shaft at leastwhen the distal sheath covers the compartment, and a retainer, includinga retention portion affixed to the principal shaft and including aplurality of acceptances adapted to receive retention members extendingfrom an end of a stent portion of the valve, and a spacer portion havinga plurality of circumferentially spaced elongated ribs, each adjacentpair of ribs defining a channel therebetween, each channel being adaptedto receive a junction at the end of the stent portion of the valve.

A method of delivering a collapsible prosthetic heart valve includesproviding a delivery device including a principal shaft around which acompartment is defined, a distal sheath adapted to selectively cover anduncover the compartment, the distal sheath extending around theprincipal shaft at least when the distal sheath covers the compartment,and a retainer including a pusher and a holder, the pusher having atleast one recess in a retention edge thereof and the holder having atleast one elongated rib, mounting in the compartment a collapsibleprosthetic heart valve having a stent portion including a plurality ofjunctions at an end thereof and a plurality of cell openings definedtherein, the valve being mounted so that at least one of the junctionsis positioned in the at least one recess and the at least one rib ispositioned in at least one of the cell openings, moving the distalsheath to cover the compartment and the valve, inserting the deliverydevice in a patient to position the valve at a target location, anddeploying the valve by moving the distal sheath to uncover thecompartment and the valve.

The method may also include sliding at least one of the pusher and theholder towards another of the pusher and the holder, thereby capturingthe junctions positioned therebetween. The principal shaft may beaffixed to the holder, the pusher may be affixed to a pusher shaft, andthe sliding step may include sliding at least one of the principal shaftand the pusher shaft relative to another of the principal shaft and theholder shaft. The method may also include, after the sliding step,temporarily fixing the position of the pusher relative to the holder.The method may also include, after the inserting step, releasing atleast one of the pusher and the holder for movement relative to oneanother. The method may also include sliding at least one of the pusherand the holder away from another of the pusher and the holder, therebyreleasing the junctions positioned therebetween.

BRIEF DESCRIPTION OF THE DRAWINGS

Various embodiments of the present invention will now be described withreference to the appended drawings. It is appreciated that thesedrawings depict only some embodiments of the invention and are thereforenot to be considered limiting of its scope.

FIG. 1 is a side view of a conventional transfemoral delivery device fora collapsible prosthetic heart valve;

FIG. 2A is a longitudinal cross-section of one embodiment of atransfemoral delivery device for a collapsible prosthetic heart valve inaccordance with the present invention;

FIG. 2B is a side elevation of the inner shaft and retainer of thedelivery device shown in FIG. 2A;

FIG. 2C is an enlarged side elevation of the retainer shown in FIG. 2B;

FIG. 3A is an enlarged side elevation of another embodiment of aretainer suitable for use in the delivery device of FIG. 2A, showing thestent portion of a valve assembled thereto;

FIG. 3B is an enlarged side elevation of the retainer of FIG. 3A,showing a retainer cone but not the stent portion of the valve;

FIG. 4 is an enlarged side elevation of an embodiment of a retainer witha slidable portion suitable for use in the delivery device of FIG. 2A;

FIG. 5 is a lateral cross-section of a holder portion of a retainersuitable for use in the delivery device of FIG. 2A;

FIG. 6A is a lateral cross-section of another holder portion of aretainer suitable for use in the delivery device of FIG. 2A;

FIG. 6B is a detailed view in cross-section showing a rib of the holderportion of FIG. 6A;

FIG. 7A is a lateral cross-section of a pusher portion of a retainersuitable for use in the delivery device of FIG. 2A;

FIG. 7B is a detailed view in cross-section showing a recess of thepusher portion of FIG. 7A;

FIG. 8 is a longitudinal cross-section of another embodiment of atransfemoral delivery device for a collapsible prosthetic heart valvehaving a slidable holder portion;

FIG. 9 is a longitudinal cross-section of a further embodiment of atransfemoral delivery device for a collapsible prosthetic heart valvehaving a slidable pusher portion;

FIG. 10A is a longitudinal cross-section of the distal portion of atransfemoral delivery device for a collapsible prosthetic heart valveincluding a pusher portion having a single circumferential recess;

FIG. 10B is an enlarged longitudinal cross-section of the pusher portionshown in FIG. 10A;

FIG. 11 is an enlarged longitudinal cross-section showing a retainerwith a slidable portion suitable for use in the delivery device of FIGS.8 and 9;

FIG. 12 is a longitudinal cross-section of a transapical delivery devicefor a collapsible prosthetic heart valve having a slidable portion; and

FIG. 13 is a perspective view of a retainer suitable for use in atransfemoral or transapical delivery device for a conventionalcollapsible heart valve having retention members.

DETAILED DESCRIPTION

As used herein, the terms “proximal” and “distal” are to be taken asrelative to a user (e.g., a surgeon or an interventional cardiologist)using the disclosed delivery devices. “Proximal” is to be understood asrelatively close to the user and “distal” is to be understood asrelatively farther away from the user.

Referring to FIG. 1, an exemplary prior art transfemoral delivery device1 for a collapsible prosthetic heart valve has a distal sheath 2surrounding and slidably coupled to an inner shaft 3. The inner shaft 3is attached to a retainer 4 having a plurality of acceptances 5. Theacceptances 5 are adapted to receive a plurality of retention members 7on the stent portion 6 of a collapsible prosthetic heart valve tothereby couple the valve to the retainer 4.

The acceptances 5 hold the retention members 7 during unsheathing of thevalve, as friction forces between the valve and the distal sheath 2 actto pull the retention members against the closed end of the acceptances5. The acceptances 5 also hold the retention members 7 duringresheathing of the valve, as friction forces between the valve and thedistal sheath 2 act to push the retention members against a constrictedopen neck of the acceptances 5. The pushing and pulling on the retentionmembers 7 during unsheathing and resheathing of the valve may damage ordeform the stent struts that support the retention members.

Referring now to FIGS. 2A-2C to illustrate the structure and function ofthe present invention, an exemplary transfemoral delivery device 10 fora collapsible prosthetic heart valve includes a catheter assembly 16 fordelivering the heart valve to and deploying the heart valve at a targetlocation. The delivery device 10 extends from a proximal end 12 to adistal end 14. The catheter assembly 16 is adapted to receive acollapsible prosthetic heart valve in an assembled condition in acompartment 23 defined around an inner shaft 26 between a retainer 30affixed to the inner shaft and the proximal end of an atraumatic tip 31.The inner shaft 26 extends from a hub 20 to the atraumatic tip 31, andincludes a central lumen 27 adapted to receive a guide wiretherethrough. The guide wire may exit the distal end 14 of the deliverydevice 10 through a central bore 25 in the tip 31, which is axiallyaligned with the lumen 27.

A distal sheath 24 surrounds the compartment 23 and is slidable relativeto the inner shaft 26 such that it can selectively cover or uncover acollapsed prosthetic heart valve positioned in the compartment. An outershaft 22 is connected at one end to the proximal end of the distalsheath 24 and at its other end to a hub 21. The distal end 29 of thedistal sheath 24 abuts a conical surface of the tip 31 when the distalsheath fully covers the compartment 23, and is spaced apart from the tip31 when the compartment 23 is at least partially uncovered. A hemostasisvalve 28 (shown, for example, in FIG. 2A) has an internal gasket adaptedto create a seal between the inner shaft 26 and the proximal end of theouter shaft 22. The hubs 20 and 21 optionally may be affixed to anoperating handle (not shown) adapted to allow a user to selectivelyslide the outer shaft 22 relative to the inner shaft 26 and to provide amechanical advantage to the user to help overcome the friction forcesacting on the outer shaft and the distal sheath 24 during their motionrelative to the inner shaft.

The retainer 30 includes a pusher 32 located at the proximal end of theretainer and a holder 34 located at the distal end of the retainer. Thepusher 32 and the holder 34 are affixed to the inner shaft 26 so thatthey remain stationery as the distal sheath 24 is moved proximally ordistally relative to compartment 23. The pusher 32 and the holder 34 maybe formed integrally with the inner shaft 26 or may be formed separatelyand affixed to the inner shaft by adhesive, welding or any other knownjoining technique.

The pusher 32 includes a plurality of recesses 40 which extendproximally from a distal retention edge 33 thereof. The recesses 40 maybe spaced substantially equally about the outside circumferentialsurface of the pusher 32 and are configured to receive respectiveV-shaped junctions formed by the struts at the end of the stent portionof a prosthetic valve (V-shaped strut junctions are shown engaged insimilar recesses in FIG. 3A).

The holder 34 includes one or more ribs 50 projecting radially outwardfrom the outside circumferential surface of the holder. The ribs 50 areoriented in the longitudinal direction of the inner shaft 26 and may bespaced substantially equally apart such that each rib is aligned in thelongitudinal direction with a recess 40 in the pusher 32. Each recess 50is adapted to be received in a diamond-shaped cell opening locatedadjacent to the V-shaped junction formed by the struts at the end of thestent portion of a prosthetic valve (exemplary diamond shaped cellopenings are shown engaged by similar ribs in FIG. 3A).

In contrast to the prior art delivery device 1, the delivery device 10is adapted to deliver a prosthetic valve having a stent portion thatdoes not have retention members extending therefrom (e.g., the retentionmembers 7 shown in FIG. 1). Rather, a valve is retained in the deliverydevice 10 by engagement of the stent portion of the valve with therecesses 40 of the pusher 32 and the ribs 50 of the holder 34. Duringdeployment of the valve, the pusher 32 is adapted to push distally onthe V-shaped junctions of the stent portion of the valve to restrictproximal movement of the valve resulting from the friction force actingbetween the valve and the distal sheath 24 as the distal sheath iswithdrawn. During resheathing of the valve, the engagement of the ribs50 of the holder 34 in the diamond-shaped cell openings of the stentportion of the valve keeps the valve assembled to the retainer 30. Thatis, the ribs 50 apply a retention force in a proximal direction torestrict distal movement of the valve resulting from the friction forceacting between the valve and the distal sheath 24 as the distal sheathis advanced.

When a prosthetic valve is assembled in the compartment 23 with thedistal sheath 24 covering the compartment, the recesses 40 and the ribs50 are adapted to substantially limit the movement of the valvelongitudinally and rotationally relative to the retainer 30, forexample, during insertion of the delivery device into a patient. Therecesses 40 can provide a limit to longitudinal movement of the valve ina proximal direction, and can substantially fix the circumferentialpositions of the stent struts, preventing them from overlapping with oneanother and becoming otherwise entangled during the delivery of thevalve to a target location in the patient. The ribs 50 can substantiallylimit longitudinal movement of the valve in a distal direction, and canalso substantially fix the circumferential positions of the stentstruts.

To load the delivery device 10 with a collapsible prosthetic valve, auser may retract the distal sheath 24 to expose the compartment 23,collapse the valve around the inner shaft 26, and couple the proximalend of the stent portion of the valve to the pusher 32 and the holder 34of the retainer 30. To couple the stent portion of the valve to theretainer 30, a user inserts each V-shaped junction formed by the strutsat the proximal end of the stent portion of the valve into acorresponding recess 40 of the pusher 32, and aligns the valve such thateach rib 50 of the holder 34 is inserted into a correspondingdiamond-shaped cell opening located adjacent to the V-shaped junctions.The user may then slide the distal sheath 24 over the compartment 23,which holds the valve in a compressed state.

When the valve is in the assembled condition in the compartment 23, theend of the stent portion opposite the end at which the valve structureis located preferably is attached to the retainer 30 (or any of theretainer embodiments disclosed herein), such that the end of the valvethat is to be deployed first (e.g., the annulus end of the valve) islocated near the atraumatic tip 31.

To use the delivery device 10 to deploy a prosthetic valve that has beencompressed and inserted in the compartment 23 and covered by the distalsheath 24, the user may slide the outer shaft 22 and the attached distalsheath proximally relative to the inner shaft 26 to retract the distalsheath from the compartment 23. When the distal sheath 24 has been onlypartially retracted, the compartment 23 will not be fully exposed andthe valve will not be fully deployed. Rather, the proximal end of thevalve will still be engaged with the pusher 32 and the holder 34 of theretainer 30 and covered by the distal sheath 24. In this condition, thevalve may be resheathed if desired, such as for repositioning the valverelative to the native valve annulus. Resheathing may be accomplished bysliding the distal sheath 24 back over the portion of the stent that hasexpanded, thereby recollapsing same into the compartment 23.

When the distal sheath 24 is fully retracted from the compartment 23,the valve will be fully unsheathed, and the proximal end of the stentportion of the valve will self-expand and become disengaged from thepusher 32 and the holder 34 of the retainer 30. Disengagement of thestent portion of the valve from the retainer 30 will thus release thevalve from the catheter assembly 16.

In a variant of the delivery device 10, the recesses 40 may be omittedfrom the pusher 32. In such an embodiment, the retention edge 33 of thepusher 32 may push distally on the V-shaped junctions of the stentportion of the valve during deployment of the valve into a patient.

FIGS. 3A and 3B show a retainer 130 in accordance with anotherembodiment of the invention, which is suitable for use with the catheterassembly 16 described above. The retainer 130 is similar to the retainer30 described above, except that the pusher 132 and the holder 134 arespaced closer together, the transition between the pusher 132 and theinner shaft 126 includes a gradual slant rather than an abrupt change indiameter, and the holder 134 includes a distal conical end 136.Furthermore, FIG. 3A shows a stent portion 106 of a collapsibleprosthetic heart valve engaged with the retainer 130.

As described above with reference to FIGS. 2A-2C, the stent portion 106of the valve includes V-shaped junctions 107 formed by the struts at oneend thereof that engage with the recesses 140 in the pusher 132. Eachrecess 140 may be slightly wider in the circumferential direction thanthe compressed width of a corresponding junction 107 when the stentportion 106 is in an assembled condition. However, the uncompressedwidth of a junction 107 may be slightly wider in the circumferentialdirection than a corresponding recess 140, such that the junction isslightly compressed in the circumferential direction when inserted intoa recess.

Each recess 140 may have a U-shaped profile that approximately matchesthe V-shape of a corresponding junction 107, such that the junctioncontacts the pusher 132 at the closed end of the recess and at each sideat the open end of the recess. Alternatively, each recess 140 mayclosely match the shape of the corresponding junction 107, such that thecontact between each recess and junction occurs over a greater portionof the junction 107 and the recess than is shown in FIG. 3A.

The stent portion 106 of the valve also includes diamond-shaped cellopenings 108 located adjacent to the V-shaped junctions 107 that engagewith the ribs 150 of the holder 134. Each rib 150 may be slightlynarrower in the circumferential direction than the maximum width nearthe center of a corresponding diamond-shaped cell opening 108 when thestent portion 106 is in the assembled condition. However, the width atthe longitudinal ends of a cell opening 108 may be slightly narrower inthe circumferential direction than the width of a corresponding rib 150,such that the ribs tend to expand the cell openings 108 in thecircumferential direction at the points at which the ribs contact thestent portion 106. As shown in FIG. 3A, each rib 150 may have straightlateral edges that are substantially parallel to the longitudinal axisof the retainer 130, such that each rib contacts the stent portion 106near a junction 107, thereby limiting the distal movement of the stentportion 106 relative to the retainer.

Referring now to FIG. 4, a retainer 230 in accordance with anotherembodiment of the invention is shown. The retainer 230 is suitable foruse with the catheter assembly 16 described above with reference to FIG.2A. The retainer 230 is similar to the retainer 130 described above withreference to FIGS. 3A and 3B, except that the shape of the ribs 250 ismore closely matched to the corresponding diamond-shaped cell openingsin the stent portion of a collapsible prosthetic heart valve, and thepusher 232 and/or the holder 234 are longitudinally slidable relative toone another.

The holder 234 includes ribs 250 that have lateral edges 251 that areangled relative to the longitudinal axis of the retainer 230, such thatthe angle formed by the lateral edges 251 of a rib 250 approximatelymatches the angle formed by the struts of a corresponding junction.Accordingly, each rib 250 is narrower at its proximal end than at itsdistal end, such that each rib contacts the stent portion of acollapsible prosthetic heart valve along a longer portion of arespective diamond-shaped cell opening than the ribs 150 of the retainer130.

The pusher 232, the holder 234 or both may be longitudinally slidable sothat they may be moved closer to one another or further apart. For auser to control the relative longitudinal sliding of the pusher 232 andthe holder 234, the pusher may be fixedly connected to an inner shaft226 that extends to the proximal end of the delivery device, and theholder may be fixedly connected to a holder shaft 229 that also extendsto the proximal end of the delivery device. The holder shaft 229 may bedisposed within the inner shaft 226 for sliding movement relative tosame. The inner shaft 226 and the holder shaft 229 may be affixed attheir proximal ends to respective hubs and/or to an operating handlethat allows the user to slide the inner shaft and the holder shaftrelative to one another. A central shaft 227 may provide a fixedconnection between the distal tip of the delivery device and the holdershaft 229. The central shaft 227 may extend from the distal tip of thedelivery device proximally to a location within the holder shaft 229adjacent the retainer 230, or may extend all the way to the proximal endof the delivery device. The central shaft 227 may have a lumen for aguide wire (not shown) therethrough.

To load a collapsible prosthetic valve into the valve compartment of adelivery device incorporating the retainer 230, a user may engage thestent portion of the collapsed valve into the pusher 232 and the holder234 by inserting the V-shaped junctions into the recesses 240 andassembling the diamond-shaped cell openings around the ribs 250. Theuser may then pinch or lock the V-shaped junctions between the recesses240 and the ribs 250 by sliding the holder 234 and/or the pusher 232towards one another. Subsequently, the distal sheath may be slid overthe compartment to hold the valve in the compressed state.

To deploy the valve, the distal sheath may be slid proximally togradually uncover the collapsed valve held in the compartment of thedelivery device. As portions of the valve are exposed, they will beginto expand radially. Typically, the annulus end of the valve is exposedfirst. After expansion of the annulus end of the valve (i.e., partialdeployment of the valve), it may be desired to reposition the valve inthe patient's aortic annulus. However, for the user to be able toresheathe a partially-deployed valve, a portion of the valve must remaincollapsed inside of the distal sheath. When using delivery devices thatdo not have a pusher and a holder that are moveable relative to oneanother to retain the valve, the user may accidentally fully deploy thevalve before the annulus end of the valve is properly located in thepatient's aortic annulus. With delivery devices incorporating theretainer 230, however, the user may pull the holder shaft 229proximately relative to the inner shaft 226, thereby squeezing the stentportion of the valve between the pusher 232 and the holder 234. Thissqueezing action may keep the valve assembled to the retainer 230 andprevent the accidental full deployment of the valve as the distal sheathis withdrawn. As such, the use of retainer 230 may allow the opportunityto resheathe and reposition the valve prior to full deployment.

To release the valve into the desired position in the patient (i.e.,fully deploy the valve), the user may slide the holder shaft 229distally relative to the inner shaft 226 to separate the holder 234 fromthe pusher 232. As the holder 234 and the pusher 232 move apart, thevalve is released and can self expand when the distal sheath is fullywithdrawn from covering the compartment.

Referring now to FIG. 5, a cross-section of an exemplary embodiment of aholder 334 of a retainer according to the invention is shown. The holder334 is similar to the holders 34, 134, and 234 described above, exceptthat the holder 334 only includes three ribs 350. The holder 334 isadapted to fit into some of the diamond-shaped cell openings of thestent portion of a prosthetic valve, while circumferentially adjacentcell openings remain empty. For example, when the stent portion of aprosthetic valve having twelve diamond-shaped cell openings spaced aboutthe circumference of the valve is loaded onto the holder 334, only everyfourth cell opening is engaged with a rib 350, while the remaining cellopenings remain empty. Although the holder 334 is shown with three ribs350, it may have any number of ribs, including, for example, 2, 4, 6, 8,9, 10, 12, or 16 ribs, depending on the number of cell openings aroundthe circumference of the valve.

Referring now to FIG. 6A, a cross-section of another exemplaryembodiment of a holder 434 of a retainer according to the invention isshown. The holder 434 is similar to the holder 334 described above,except that the holder 434 includes six ribs 450, such that when thestent portion of a valve having twelve diamond-shaped cell openingsspaced about the circumference of the valve is mounted onto the holder,only every other cell opening is engaged with a rib, while the othercell openings remain empty.

Referring now to FIG. 6B, an enlarged cross-section of an exemplaryembodiment of a rib 450 a is shown. The rib 450 a is similar to the rib450 shown in FIG. 6A, except that the rib has a cross-sectional shapethat includes an undercut, such that each lateral edge 451 that extendsgenerally in the longitudinal direction of the retainer projects outwardfrom the outer surface of the holder 434 at an angle of less than 90°.Having the ribs 450 a include such an undercut may increase the abilityof the ribs to grip onto the struts of the stent portion of the valve,such that when the holder and a pusher are moved towards one another tolock the valve into the retainer, there may be interference between thestruts and the ribs to help prevent the stent portion from sliding offof the ribs, thereby helping to prevent premature deployment of thevalve while the holder and pusher are positioned closely together.

Any portion of the longitudinal length of the rib 450 a may be undercut,and the remainder of the length of the rib may not be undercut (i.e., anon-undercut portion of the lateral edge 451 projects outward from theouter surface of the holder 434 at an angle of at least 90°). Forexample, each rib 450 a may have undercut lateral edges 451 only at themost proximal 10-20% of the longitudinal length of the rib. In retainerembodiments having ribs including substantially longitudinally orientedlateral edges, such as the ribs shown in FIGS. 2B, 2C, 3A, and 3B, onlythe most proximal 10-20% of the longitudinal length of the rib may be incontact with the struts of the stent portion of the valve when the valveis engaged with the retainer, so that may be the only portion of the ribat which an undercut may enhance the stent-gripping ability of the rib.

A cross-section of an exemplary embodiment of a pusher 432 of a retaineraccording to the invention is shown in FIG. 7A. The pusher 432 issimilar to the pushers 32, 132, and 232 described above, except that thepusher 432 includes eight recesses 440. It will be appreciated, however,that the pusher 432 may include any number of recesses, including, forexample, 2, 4, 6, 8, 9, 10, 12, or 16 recesses, depending on the numberof V-shaped junctions formed at the end of the stent portion of thevalve.

Referring now to FIG. 7B, an enlarged cross-section of an exemplaryembodiment of a recess 440 a is shown. The recess 440 a is similar tothe recess 440 shown in FIG. 7A, except that the recess has across-sectional shape that includes an undercut, such that each lateraledge 441 that extends generally in the longitudinal direction of theretainer projects inward from the outer surface of the pusher 432 at anangle of less than 90°. Having the recesses 440 a include such anundercut may increase the ability of the recesses to grip onto theV-shaped junctions of the stent portion of the valve, such that when thepusher and a holder are moved towards one another to lock the valve intothe retainer, there may be interference between the V-shaped junctionsand the recesses to help prevent the stent portion from sliding out fromthe recesses, thereby helping to prevent premature deployment of thevalve while the holder and pusher are positioned closely together.

Any portion of the longitudinal length of the recess 440 a be undercut,and the remainder of the length of the recess may not be undercut (i.e.,a non-undercut portion of the lateral edge 441 projects inward from theouter surface of the pusher 432 at an angle of at least 90°). Forexample, each recess 440 a may have undercut lateral edges 441 only atthe most distal 10-20% of the longitudinal length of the recess. Inretainer embodiments having recesses including substantiallylongitudinally oriented lateral edges, such as the recesses shown inFIGS. 3A, 3B, and 4, only the closed end and the most distal 10-20% ofthe longitudinal length of the recess may be in contact with theV-shaped junctions of the stent portion of the valve when the valve isengaged with the retainer, so these may be the only portions of therecess at which an undercut may enhance the stent-gripping ability ofthe recess.

Referring now to FIG. 8, an exemplary transfemoral delivery device 510for a collapsible prosthetic heart valve according to the invention isshown. The delivery device 510 is similar to the delivery device 10described above, but includes a retainer similar to the retainer 230 inwhich the pusher and holder are slidable relative to one another.

The retainer 530 of the delivery device 510 includes a pusher 532affixed to an inner shaft 526 having a hub 520 on its proximal end. Theholder 534 of the retainer 530 is affixed to a holder shaft 529 thatextends through the lumen of the inner shaft 526 to a proximal hub 525.In the embodiment shown in FIG. 8, the holder 534 is longitudinallyslidable relative to the pusher 532 to capture the proximal end of thestent portion of the valve therebetween, and thereby assemble it to theretainer 530. Although the recesses in the pusher 532 and the ribs inthe holder 534 are not shown in FIG. 8, the pusher and the holder mayhave any of the recess and rib configurations disclosed herein.

The delivery device 510 includes a distal sheath 524 surrounding acompartment 523 adapted to receive a collapsible prosthetic heart valve506 in an assembled condition around a central shaft 527 that may extendbetween a distal end of the delivery device and a location within theholder shaft 529. The central shaft 527 may provide a fixed connectionbetween the distal tip of the delivery device and the holder shaft 529.The central shaft 527 may extend from the distal tip of the deliverydevice proximally to a location within the holder shaft 529 adjacent theholder 534, or may extend all the way to the proximal end of thedelivery device. The central shaft 527 may have a lumen for a guide wire(not shown) therethrough. As with the retainer 230 described above, auser may load a valve 506 in the compartment 523 by capturing theV-shaped junctions of the stent portion of the valve between therecesses of the pusher 532 and the ribs of the holder 534 by sliding theholder proximally towards the pusher.

With the proximal end of the stent portion of the valve 506 capturedbetween the pusher 532 and the holder 534, the user may move a lockingpin 519 positioned in the hub 520 to a locked position. In the lockedposition, the locking pin 519 temporarily affixes the inner shaft 526 tothe holder shaft 529 to fix the relative positions of the pusher 532 andthe holder 534. To deploy the valve 506, the user may first withdraw thedistal sheath 524 from around the compartment 523 by sliding the hub 521proximally. Subsequently, the user may move the locking pin 519 to anunlocked position and slide the holder shaft 529 distally, and with itthe holder 534, to unclamp the valve 506 from the retainer 530 so thatthe valve can self-expand and thereby become released from the retainer.

FIG. 9 shows another exemplary transfemoral delivery device 610 for acollapsible prosthetic heart valve according to the invention. Thestructure and function of the delivery device 610 is similar to thestructure and function of the delivery device 510 described above in allrespects, except that the pusher 632 is longitudinally slidable relativeto the holder 634 to allow a user to capture the stent portion of aprosthetic valve in the retainer 630, rather than having the holderslidable relative to the pusher. Whether the pusher, the holder, or bothcomponents are configured to be slidable or fixed in a given embodimentmay depend on how the respective hubs are attached to an operatinghandle (not shown). The stent portion of a prosthetic valve may becaptured between the pusher and holder in a similar manner regardless ofwhether the pusher, the holder, or both components are configured to beslidable.

Referring now to FIGS. 10A and 10B, yet another exemplary transfemoraldelivery device 710 for a collapsible prosthetic heart valve accordingto the invention is shown. The delivery device 710 is similar to thedelivery devices 510 and 610 described above with reference to FIGS. 8and 9, respectively, except that, rather than a plurality of discreterecesses, the pusher 732 includes a single recess 740 having an annularwall 741 extending continuously around the entire circumference thereof.When a valve is assembled in the delivery device 710, the V-shapedjunctions of the stent portion of the valve may be retained by theannular wall 741 such that the V-shaped junctions do not splay radiallyoutward. The presence of the annular wall 741 in the pusher 732 may makeit easier for the pusher 732 to retain the proximal end of a valveduring loading of the valve into the delivery device 710. The pusher732, the holder 734, or both components may be slidable or fixedrelative to one another. Although the ribs in the holder 734 are notshown in FIG. 10A, the holder may have any of the rib configurationsdisclosed herein.

A retainer 830 in accordance with another embodiment of the invention isshown in FIG. 11. The retainer 830 is similar to the retainers 230, 530,630, and 730 having a movable pusher and/or holder as described above,except that the ribs 850 extend proximally from a conical end 836attached to the holder 834, rather than extending radially outward froman outer surface of the holder. Although the recesses in the pusher 832are not visible in the particular cross-section shown in FIG. 11, theholder may have recesses extending proximally from the retention edge833 that are adapted to receive V-shaped junctions of the stent portionof a collapsible prosthetic valve. The pusher 832, the holder 834, orboth components may be slidable relative to one another or fixed.

Referring now to FIG. 12, an exemplary transapical delivery device 910for a collapsible prosthetic heart valve 906 has a catheter assembly 916for delivering the heart valve to and deploying the heart valve at atarget location. The delivery device 910 extends from a proximal end 912to a distal end 914. The catheter assembly 916 is adapted to receive acollapsible prosthetic heart valve in an assembled condition in acompartment 923 defined around a support shaft 928 and covered by adistal sheath 924.

The support shaft 928 extends from a holder 934 fixed at the distal endof the support shaft to a retainer 911 fixed at the proximal end of thesupport shaft. The retainer 911, in turn, is connected to an outer shaft922 having a hub 921 on its proximal end. The holder 934 and a pusher932 are adapted to hold a collapsible prosthetic valve in thecompartment 923 defined around the support shaft 928. The pusher 932 maybe affixed to a pusher shaft 929 that extends through the support shaft928 and the outer shaft 922 to a hub 925. An inner shaft 926 may extendthrough the pusher shaft 929 from a hub 920 at its proximal end to aconnection to an atraumatic tip 931 at the distal end 914 of thedelivery device 910.

The distal sheath 924 surrounds compartment 923 and is slidable relativeto the support shaft 928 such that it can selectively cover or uncover acollapsed prosthetic valve 906 positioned in the compartment. The distalsheath 924 is affixed at its distal end to the tip 931. The proximal end915 of the distal sheath 924 may abut a conical surface 917 of theretainer 911 when the distal sheath fully covers the compartment 923, asshown in FIG. 12, and is spaced apart from the conical surface 917 whenthe compartment 923 is at least partially uncovered.

In the embodiment shown in FIG. 12, the pusher 932 and/or the holder 934may slide relative to one another to capture the distal end of the stentportion of the valve 906 therebetween. Although the recesses in thepusher 932 and the ribs on the holder 934 are not shown in FIG. 12, thepusher and the holder may have any of the recess and rib configurationsdisclosed herein. As with the delivery devices 510 and 610 describedabove, a user may load a valve 906 in the compartment 923 by capturingthe V-shaped junctions of the stent portion of the valve between therecesses of the pusher 932 and the ribs of the holder 934 by sliding thepusher and/or the holder longitudinally towards one another.

The delivery device 910 may include a locking pin 919 adapted, in alocked position, to temporarily affix the outer shaft 922 (and with it,the support shaft 928) to the pusher shaft 929 and thereby fix therelative positions of the pusher 932 and the holder 934. With the distalend of the stent portion of the valve 906 captured between the pusherand the holder, the user may move the locking pin 919 to a lockedposition to fix the relative positions of the pusher and the holder.

To deploy the valve 906, the user may first withdraw the distal sheath924 from around the compartment 923 by sliding the inner shaft 926distally relative to the outer shaft 922 and the pusher shaft 929.Subsequently, the user may move the locking pin 919 to an unlockedposition, and may slide the pusher 932 and the holder 934 longitudinallyaway from one another to unclamp the valve 906 from within the retainer930 so that the valve can self-expand and thereby become released fromthe delivery device 910.

Referring now to FIG. 13, a retainer 1030 in accordance with anotherembodiment of the invention is shown. The retainer 1030 is adapted toretain and align the stent portion of a conventional prosthetic valve,such as the stent portion 6 shown in FIG. 1. The retainer 1030 may beincorporated either in a transfemoral delivery device, such as thedelivery device 10 described above, with the valve extending distallyfrom the retainer, or in a transapical delivery device, such as thedelivery device 910 described above, with the valve extending proximallyfrom the retainer.

The retainer 1030 includes a retention portion 1032 affixed to an innershaft 1026, the retention portion including a plurality of acceptances1035 adapted to receive retention members of a conventional valve, suchas the retention members 7 shown in FIG. 1. The retainer 1030 alsoincludes a spacer portion 1034 affixed to the retention portion 1032,the spacer portion including a plurality of ribs 1050 extending in alongitudinal direction, each adjacent pair of ribs defining a channel1052 therebetween. The ribs 1050 preferably are spaced uniformly in acircumferential direction around the spacer portion 1034.

To load the stent portion of a conventional prosthetic valve into theretainer 1030 for delivery into a patient, a user may insert theretention members of the valve into the acceptances 1035, and theV-shaped junctions at the aortic end of the stent into respectivechannels 1052. The channels 1052 that are longitudinally aligned with anacceptance 1035 can receive the V-shaped junction aligned in thelongitudinal direction with a retention member.

In a conventional delivery system, the stent portion of a conventionalprosthetic valve can become twisted during delivery of the valve to adesired location in a patient, and the stent struts can bind against thedistal sheath covering the valve, potentially deforming or damaging thestruts and/or increasing the force required to unsheathe the valve.Compared to a conventional retainer, the retainer 1030 can keep theV-shaped junctions of the stent struts aligned during delivery of thevalve within a patient, thereby preventing damage to the valve andminimizing the force needed for unsheathing and deployment.

Although the various retainer embodiments have been described here inconnection with retaining for deployment a prosthetic valve having acollapsible stent structure, all of the retainer embodiments may be usedfor other purposes. In particular, the various embodiments of retainersmay be used to retain conventional collapsible stents that do notcontain a valve structure.

Although the invention herein has been described with reference toparticular embodiments in which the annulus end of a prosthetic valve isdeployed first, it is to be understood that the invention contemplatesembodiments in which the aortic end of a valve is deployed first. Insuch embodiments (not shown), the annulus end of the stent portion ofthe valve may be engaged with a retainer, while the aortic end of thestent may be remote from the retainer and may be unsheathed first.

Although the invention herein has been described with reference toparticular embodiments, it is to be understood that these embodimentsare merely illustrative of the principles and applications of thepresent invention. It is therefore to be understood that numerousmodifications may be made to the illustrative embodiments and that otherarrangements may be devised without departing from the spirit and scopeof the present invention as defined by the appended claims.

It will be appreciated that the various dependent claims and thefeatures set forth therein can be combined in different ways thanpresented in the initial claims. It will also be appreciated that thefeatures described in connection with individual embodiments may beshared with others of the described embodiments.

INDUSTRIAL APPLICABILITY

The present invention enjoys wide industrial applicability including,but not limited to, delivery devices for collapsible prosthetic heartvalves and methods of delivering collapsible prosthetic heart valves.

The inventino claimed is:
 1. A delivery device for a collapsibleprosthetic heart valve, the delivery device comprising: a catheterassembly including a principal shaft around which a compartment isdefined, the compartment being adapted to receive the valve in anassembled condition, the catheter assembly further including a distalsheath adapted to selectively cover and uncover the compartment and thevalve, the distal sheath extending around the principal shaft at leastwhen the distal sheath covers the compartment; and a retainer,including: a retention portion fixedly connected to the principal shaftand including a plurality of circumferentially spaced acceptances eachhaving a closed end and an open end spaced apart from the closed end bya first distance in a longitudinal direction of the catheter assembly;and a spacer portion fixedly connected to the principal shaft and havinga plurality of circumferentially spaced elongated ribs connected to andextending from an end of the retention portion in the longitudinaldirection, each adjacent pair of elongated ribs defining a channeltherebetween, the channels including: a first group and second groupthat together comprise all of the channels, the first group containing afirst positive number of the channels and the second group containing aremaining positive number of the channels that is not in the firstgroup, the first group of the channels each having an open end and aclosed end spaced apart from one another by a second distance in thelongitudinal direction that is greater than the first distance, thesecond group of the channels each having a first open end and a secondopen end spaced apart from one another in the longitudinal direction bythe second distance, the second open end of each of the second channelsbeing the open end of a corresponding one of the acceptances, the firstopen end of each of the second channels being spaced apart from theclosed end of the corresponding one of the acceptances by a thirddistance in the longitudinal direction that is greater than the firstdistance and greater than the second distance.
 2. The delivery device ofclaim 1, wherein the acceptances are configured to receive correspondingretention members of the collapsible prosthetic heart valve therein, theacceptances and the retention members being equal in number.
 3. Thedelivery device of claim 1, wherein the principal shaft is elongated inthe longitudinal direction, and the elongated ribs each extend in thelongitudinal direction.
 4. The delivery device of claim 1, wherein theprincipal shaft is elongated along a longitudinal axis, and theelongated ribs are spaced uniformly about the longitudinal axis in acircumferential direction around the spacer portion.
 5. The deliverydevice of claim 1, wherein each acceptance is aligned in thelongitudinal direction with a corresponding one of the channels.
 6. Adelivery device, comprising: a collapsible prosthetic heart valve havinga stent portion including a plurality of junctions defining an end ofthe stent portion and a plurality of cell openings defined therein, andretention members extending from some of the junctions past the end ofthe stent portion of the valve; a catheter assembly including aprincipal shaft around which a compartment is defined, the collapsibleprosthetic heart valve positioned in the compartment in an assembledcondition, the catheter assembly further including a distal sheathadapted to selectively cover and uncover the compartment and the valve,the distal sheath extending around the principal shaft at least when thedistal sheath covers the compartment; and a retainer, including: aretention portion fixedly connected to the principal shaft and includinga plurality of circumferentially spaced acceptances each having a closedend and an open end spaced apart from the closed end by a first distancein a longitudinal direction of the catheter assembly, each retentionmember positioned in a corresponding one of the acceptances; and aspacer portion fixedly connected to the principal shaft and having aplurality of circumferentially spaced elongated ribs connected to andextending from an end of the retention portion in the longitudinaldirection, each adjacent pair of elongated ribs defining a channeltherebetween, the channels including: a first group and second groupthat together comprise all of the channels, the first group containing afirst positive number of the channels and the second group containing aremaining positive number of the channels that is not in the firstgroup, the first group of the channels each having an open end and aclosed end spaced apart from one another by a second distance in thelongitudinal direction that is greater than the first distance, thesecond group of the channels each having a first open end and a secondopen end spaced apart from one another in the longitudinal direction bythe second distance, the second open end of each of the second channelsbeing the open end of a corresponding one of the acceptances, the firstopen end of each of the second channels being spaced apart from theclosed end of the corresponding one of the acceptances by a thirddistance in the longitudinal direction that is greater than the firstdistance and greater than the second distance.
 7. The delivery device ofclaim 6, wherein the acceptances and the retention members are equal innumber.
 8. The delivery device of claim 6, wherein the principal shaftis elongated in the longitudinal direction, and the elongated ribs eachextend in the longitudinal direction.
 9. The delivery device of claim 6,wherein the principal shaft is elongated along a longitudinal axis, andthe elongated ribs are spaced uniformly about the longitudinal axis in acircumferential direction around the spacer portion.
 10. The deliverydevice of claim 6, wherein each junction is V-shaped.
 11. The deliverydevice of claim 6, wherein each acceptance is aligned in thelongitudinal direction with a corresponding one of the channels.
 12. Thedelivery device of claim 6, wherein each junction at the end of thestent portion of the valve is separated from other ones of the junctionsby the elongated ribs.
 13. A method of delivering a collapsibleprosthetic heart valve, the method comprising: providing a deliverydevice including a principal shaft around which a compartment isdefined, the principal shaft extending along a longitudinal axis of thedelivery device extending in a longitudinal direction, a distal sheathadapted to selectively cover and uncover the compartment, the distalsheath extending around the principal shaft at least when the distalsheath covers the compartment, and a retainer including a retentionportion and a spacer portion, the retention portion fixedly connected tothe principal shaft and including a plurality of circumferentiallyspaced acceptances each having a closed end and an open end spaced apartfrom the closed end by a first distance in a longitudinal direction ofthe catheter assembly, and the spacer portion fixedly connected to theprincipal shaft and having a plurality of circumferentially spacedelongated ribs connected to and extending from an end of the retentionportion, each adjacent pair of elongated ribs defining a channeltherebetween, the channels including: a first group and second groupthat together comprise all of the channels, the first group containing afirst positive number of the channels and the second group containing aremaining positive number of the channels that is not in the firstgroup, the first group of the channels each having an open end and aclosed end spaced apart from one another by a second distance in thelongitudinal direction that is greater than the first distance, thesecond group of the channels each having a first open end and a secondopen end spaced apart from one another in the longitudinal direction bythe second distance, the second open end of each of the second channelsbeing the open end of a corresponding one of the acceptances, the firstopen end of each of the second channels being spaced apart from theclosed end of the corresponding one of the acceptances by a thirddistance in the longitudinal direction that is greater than the firstdistance and greater than the second distance; mounting in thecompartment the collapsible prosthetic heart valve having a stentportion including a plurality of junctions defining an end of the stentportion and a plurality of cell openings defined therein, and retentionmembers extending from some of the junctions past the end of the stentportion of the valve, the valve being mounted so that each retentionmember is positioned in a corresponding one of the acceptances, and eachjunction is positioned in a corresponding one of the channels; movingthe distal sheath to cover the compartment and the valve; inserting thedelivery device in a patient to position the valve at a target location;and deploying the valve by moving the distal sheath to uncover thecompartment and the valve.
 14. The method of claim 13, wherein theprincipal shaft is elongated in the longitudinal direction, and theelongated ribs each extend in the longitudinal direction.
 15. The methodof claim 13, wherein the principal shaft is elongated along alongitudinal axis, and the elongated ribs are spaced uniformly about thelongitudinal axis in a circumferential direction around the spacerportion.
 16. The method of claim 13, wherein each acceptance is alignedin the longitudinal direction with a corresponding one of the channels.17. The method of claim 13, wherein during the mounting step, eachjunction at the end of the stent portion of the valve is separated fromother ones of the junctions by the elongated ribs.
 18. The method ofclaim 13, wherein the mounting step includes mounting the valve suchthat the valve extends distally from the retainer, and the insertingstep includes inserting the delivery device into the femoral artery ofthe patient.
 19. The method of claim 13, wherein the mounting stepincludes mounting the valve such that the valve extends proximally fromthe retainer, and the inserting step includes inserting the deliverydevice into the apex of the heart of the patient.